Some of the world's best-known hackers unveiled a plan this weekend to offer free software to promote anonymous Web surfing in countries where the Internet is censored, especially China and Middle Eastern nations. An international hacker group calling itself Hacktivismo released a program on Saturday called Camera/Shy that allows Internet users to conceal messages inside photos posted on the Web, bypassing most known police monitoring methods.

In addition, "Mixter," an internationally known German hacker, said Hacktivismo was preparing in coming weeks to launch technology, which if adopted widely could allow anyone to create grassroots, anonymous networks where Internet users worldwide could access and share information without a trace.

"(Hackers) are looking for something a little more meaty to work with," spokesman "Oxblood Ruffin" said of the new social activist push by a group formerly known for creating software that has been used by other hackers to attack undefended computers.

The Hacktivismo announcement, the result of a two-year project among leading hackers worldwide, was made at H2K2, a three-day conference ending Sunday. The bi-annual event attracts an estimated 2,000 security professionals and computer activists, including the U.S. hacker elite.

Mixter's software--known as a "protocol" in technical terms--would allow ordinary computer users to set up a decentralized version of virtual private networks (VPNs). VPNs are used by governments and many companies to create secure networks that are fenced off from the public Internet.

"It's important for anyone whether they live in totalitarian country or a Western country to be anonymous," said Mixter, who lives in Munich, of his motivation to take part in the project.

Hacktivismo software works to bypass national firewalls that allow only partial access to global computer networks.

Hactivismo says it can defeat attempts to restrict Web surfing to controversial Internet news and human rights sites by disguising such sites to make them look innocuous.

The group hopes to encourage other software developers to embed the code for "Six/Four" protocol into their own programs in order to accelerate the spread of the technology worldwide. The effort will succeed only if millions of computer users begin using the programs as part of their everyday Internet Web use, providing cover to individual surfers, its proponents said.

The move is likely to heat up the battle between free speech activists and government censors in the 20 or so countries that restrict public access to the Web. It may also raise concerns among Western police agencies that fear the technology could be used by criminals to swap child pornography or by Osama bin Laden's Al-Qaeda network to plot new attacks around the globe.

Hacktivismo, or hacker activism, is just one of several grassroots software projects--including Peekabooty and Privaterra--launched recently by computer activists that seek to enable human rights workers to access censored Web sites or communicate securely.

Six/Four protocol designer Mixter said the system is named in honor of the date when Chinese authorities cracked down on democracy activists in Tiananmen Square on June 4, 1989.

Six/Four is designed so that each computer user that uses software running the protocol becomes part of the shared capacity of the network, taking a page from so-called "peer-to-peer" sharing network that gave birth to Napster and other music sharing programs such as Gnutella.

"This is going to be a guerrilla information war," Oxblood Ruffin said. "Sites will pop up for a few days and then be taken down," he said as he described a "moving war," in which computer activists react quickly to government efforts to block such programs.

In countries such as China, the Internet poses an unprecedented threat to the control that the Chinese Communist Party exercises over all other forms of media.

In the world's most populous country, where most people can't afford PCs, millions turn to Internet cafes, despite a long-running crackdown on the free-wheeling establishments by the Chinese government.

The tightening of restrictions has accelerated recently since several deadly fires, including one in a Beijing Internet cafe that killed more than 20 students in June. Sensitivity to potential sources of civil instability has been heightened by the looming leadership transition at the top of the Chinese government set for later this year.

Hacktivismo is made up of 40 or so hackers including members of the Cult of the Dead Cow, the group behind Back Orifice, which can be used by malicious hackers to gain unauthorized access to unsecured computers running Microsoft's Windows software.

Mixter developed software that was used by another teenager to launch denial of service attacks on major e-commerce sites in early 2000.

Group members have focused more recently on harnessing the energies of the computer underground to promote electronic democracy on the Internet. In the future they plan to develop programs that will allow anonymous direct e-mail, file trading and untraceable chat programs that bypass conventional Internet monitoring.

The latter is especially important in places like China, where online chat is more popular than Web surfing.

Hacktivismo leaders said that Camera/Shy was immediately available for download from its site. The program would allow visitors at public Internet cafes, popular in many countries where computers are scarce, to install the 1.2 megabyte program using a simple floppy disk.

The user installs the program on a computer, surfs the Web, then removes the program, leaving no electronic records kept of what sites were visited, said its Southern California-based designer, who goes by the hacker name "Pull."

"What this is for is for pre-suspects," Pull said. "You never become a suspect if you are using this kind of thing."